The present invention is related to Japanese patent application No. Hei. 11-359761, filed Dec. 17, 1999; 2000-56055, filed Feb. 28, 2000; the contents of which are incorporated herein by reference.
The present invention relates to an adsorption-type cooling apparatus, and more particularly to an adsorption-type cooling apparatus that is suitable for application to air conditioners.
The assignee has filed an application relating to an adsorption-type cooling apparatus containing at least four adsorption devices (Laid-open Japanese Patent Application 9-303900 hereby incorporated by reference). However, in the above-mentioned openly described invention, the apparatus is difficult to control.
In view of the above, the present invention provides an adsorption-type cooling apparatus containing four adsorption devices. The present invention provides an adsorption-type cooling apparatus comprising first, second, third, and fourth adsorption devices. These devices are filled with a coolant and contain adsorbents which adsorb evaporated coolant and desorb the adsorbed coolant during heating. Adsorption cores provide heat exchange between the adsorbents and a heat medium, and evaporation and condensation cores provide heat exchange between heating medium and the coolant. A cooling device in which heating medium cooled in the evaporation and condensation cores circulates and cools the object of cooling. A heating means supplies a high-temperature heat medium to the first-fourth adsorption devices. A cooling means supplies a low-temperature heat medium which has a temperature lower than that of the high-temperature heat medium to the first-fourth adsorption devices. Also, a switching control means is provided which switches between multiple states. In a first state, a heat medium is circulated between the cooling device and evaporation and condensation cores of the first and second adsorption devices. The low-temperature heat medium is circulated to the adsorption core of the first adsorption device and heating medium exiting the cooling device is circulated to the adsorption core of the second adsorption device. Meanwhile, the high-temperature heat medium is circulated to the adsorption cores of the third and fourth adsorption devices and the low-temperature heat medium is circulated to the evaporation and condensation cores of the third and fourth adsorption devices. In a second state, a heat medium is circulated between the cooling device and evaporation and condensation cores of the first and second adsorption devices and the low-temperature heat medium is circulated to the adsorption cores of the first and second adsorption devices. Meanwhile the high-temperature heat medium is circulated to the adsorption cores of the third and fourth adsorption devices and the low-temperature heat medium is circulated to the evaporation and condensation cores of the third and fourth adsorption devices. In a third state, the low-temperature heat medium is supplied to the inlet openings of evaporation and condensation cores of the first and second adsorption devices and the high-temperature heat medium is supplied to inlet openings of the adsorption cores of the first and second adsorption devices. Meanwhile, the low-temperature heat medium is supplied to the inlet openings of the adsorption cores of the third and fourth adsorption devices and heating medium exiting the cooling device is supplied to the evaporation and condensation cores of the third and fourth adsorption devices. In a fourth state, the low-temperature heat medium is circulated to the evaporation and condensation cores of the first and second adsorption devices and the high-temperature heat medium is circulated to the adsorption cores of the first and second adsorption devices. Meanwhile, the low-temperature heat medium is circulated to the adsorption cores of the third and fourth adsorption devices and when the evaporation and condensation cores of the third and fourth adsorption devices were filled with heating medium that exited the cooling device, the circulation of this heat medium is terminated. In a fifth state, a heat medium is circulated between the cooling device and evaporation and condensation cores of the third and fourth adsorption devices, the low-temperature heat medium is circulated to the adsorption core of the third adsorption device, and heating medium exiting the cooling device is circulated to the adsorption core of the fourth adsorption device. Meanwhile, the high-temperature heat medium is circulated to the adsorption cores of the first and second adsorption devices and the low-temperature heat medium is circulated to the evaporation and condensation cores of the first and second adsorption devices. In a sixth state (VI), a heat medium is circulated between the cooling device and evaporation and condensation cores of the third and fourth adsorption devices and the low-temperature heat medium is circulated to the adsorption cores of the third and fourth adsorption device. Meanwhile, the high-temperature heat medium is circulated to the adsorption cores of the first and second adsorption devices and the low-temperature heat medium is circulated to the evaporation and condensation cores of the first and second adsorption devices. In a seventh state (VII), the low-temperature heat medium is supplied to evaporation and condensation cores of the third and fourth adsorption devices and the high-temperature heat medium is supplied to the inlet openings of adsorption cores of the third and fourth adsorption device. Meanwhile, low-temperature heat medium is supplied to the inlet openings of the adsorption cores of the first and second adsorption devices and heating medium exiting the cooling device is supplied to the evaporation and condensation cores of the first and second adsorption devices. In an eighth state (VIII), the low-temperature heat medium is circulated to the evaporation and condensation cores of the third and fourth adsorption devices and the high-temperature heat medium is circulated to the adsorption cores of the third and fourth adsorption device. Meanwhile, the low-temperature heat medium is circulated to the adsorption cores of the first and second adsorption devices and when the evaporation and condensation cores of the first and second adsorption devices were filled with heating medium, exiting the cooling device, circulation of this heat medium is terminated. Accordingly, the switching control means has a first switching control pattern in which the states are switched in the following order: first state (I)xe2x86x92second state (II)xe2x86x92third state (III)xe2x86x92fourth state (IV)xe2x86x92fifth state (V)xe2x86x92sixth state (VI)xe2x86x92seventh state (VII)xe2x86x92eighth state (VIII)xe2x86x92first state (I).
As a result, heating medium flowing out of the cooling device which was cooling the adsorption cores in the first and fifth states is supplied to the evaporation and condensation cores undergoing the adsorption process, without being supplied to the adsorption cores, in the second and sixth states. For this reason, the supply of heating medium that has been heated while cooling the adsorption cores to the evaporation and condensation cores undergoing the adsorption process in the next stage can be prevented. Therefore, heating of the evaporation and condensation cores undergoing the adsorption process in the next stage can be prevented in advance. As a result, it is possible to prevent the loss of cooling capacity of the adsorption-type cooling apparatus. Also, the outflow temperature fluctuation is reduced by two-stage adsorption devices. Moreover, water hammering is prevented by switching valves.
In another aspect, the switching control means has a second switching control pattern in which the states are switched in the following order: fourth state (IV)xe2x86x92seventh state (VII)xe2x86x92eighth state (VIII)xe2x86x92third state (III)xe2x86x92fourth state (IV).
As a result, if the second control pattern is implemented when a large cooling capacity is required, the cooling capacity of two adsorption devices can be taken out of the cooling device and the coefficient of performance of the adsorption-type cooling apparatus can be increased.
In another aspect, the switching control means switches the states in the following order: first state (I)xe2x86x92third state (III)xe2x86x92fourth state (IV)xe2x86x92fifth state (V)xe2x86x92seventh state (VII)xe2x86x92eighth state (VIII)xe2x86x92first state (I), when the operation time of said first and fifth states (I, V) is extended.
As a result, if the first and fifth states are extended, the caloric value of adsorbents located inside the adsorption devices is decreased. For this reason, the transition from the first state to the fifth state or the transition from the fifth state to the first state can be rapidly conducted. without implementing the second and sixth states. Therefore, the time period in which the adsorption-type cooling apparatus demonstrates cooling capacity can be extended which increases the efficiency of the adsorption-type cooling apparatus.
In another aspect, the flow rate of heating medium supplied to the evaporation and condensation cores in the third state (III) or seventh state (VII) is greater than the flow rate of heating medium supplied to the evaporation and condensation cores in the first state (I) or fifth state (V).
As a result, the operation time of the third state (III) or seventh state (VII) can be shortened. Therefore, the time period during which the adsorption-type cooling apparatus demonstrates cooling capacity can be extended, and the cooling efficiency and coefficient of performance of the adsorption-type cooling apparatus can be increased.
In another aspect, the switching control means controls heating medium flow by controlling the valves switching heating medium and flow pumps circulating heating medium flow. When the valves are switched, the switching control means controls the pumps to terminate the circulation of heating medium to the switched valves. As a result, the action of a large force created by water impact (water hammer) on valves when the valves are switched is prevented.
In another aspect, a check valve is installed inside heating medium channel through which heating medium flows, in a position in which heating medium flows in one direction only. As a result, the backward flow of heating medium that was pushed in by the pump pressure can be prevented even when the pumps are stopped. Therefore, the replacement of heat medium can be conducted quickly and accurately and the adsorption-type cooling apparatus can demonstrate its capacity in full.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. In the drawings: